Casing wrench



' n. A. WILSON.

CASING WRENCH. APPLICATION FILE!) JUNE 6.1921.

1,418,767. I a ente June. 6, 1922.

nears ROBERT a. WILSON, on DALLAS, TEXAS, AssIGnon 'ro enrnnnson oonromn TION, or names, Twins. n. conronntriolv or DELAWARE.

CASING WRENCH.

Specification of Letters Patent. Patentefi June 6, 1922 Application filed June 6, 1921. 'Serial No. 475,471.

To oil in hom it may concern Be it known that I, ROBERT A. lViLsoN, a citizen of the United States, residing Dallas, in the county of Dallas and State of Texas, have invented certain new and useful Improvements in (lasing Wrenches, of which the following is a specification:

This invention relates to new and useful improvements in casing wrenches.

The object of the invention is to provide a vreneh for exerting a tight gripping action without a crushing effect, thus being particularly useful for work on well casing or other comparatively thin pipe or tubing.

A particular advantage of the invention lies in .a pivoted gripping shoe having teeth or dies projecting from its ggripping surface and means for swinging the shoe into gripping engagement with a curved surface; whereby the dies dig into the curved surface and the pressure is distributed over an amplified area and crushing avoided. The re sult of this is a positive gripping action with a minimum slippage and when the wrench is rotated Or swung the shoe exerts a torsional grip on the curved surface. Another feature lies in means: for swinging the shoe and exerting a gradual pressure on the same.

A construction designed to carry out the invention will be hereinafter described together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to theaccompanying drawings, in which an example of the invention is shown and wherein:

Fig. 1 is a longitudinal cross sectional view of a wrench constructed in accordance with my invention, and

Fig. 2 is a longitudinal sectional view taken on the line 22 of Fig. 1.

In the drawing the numeral 10 designates a aw which is formed with a concaved seat and at each of its outer ends with a pair of faced ears 12. A latch link 13 has its ends perforated and engaged in the ears 12 so as to receive bolts 14 one of which is removable, whereby the link may be swung outwardly to release or apply the wrench.

The jaw is formed with an enlarged chamher or cavity 15 as is best shown in Fig. 1. A curved shoe 16 has one end bifurcated so as to straddle the reduced ends 13 of the link and to be pivoted on the bolt 14 between the cars 12 as is indicated in the drawing. At

with alip positioned to engage a stop lug ject heyondthe inner surface of the shoe so.

as to bite into the surface of the curved article A, which is gripped by the wrench.

For swinging the shoe in the axis a cam 20 ismounted on a pivot bolti21 in the chamber 15. This camhasa-rcuate working faces 22,011 each side of its center and disposed eccentrically with relation to the pivot bolt 21. in either direction one of its e'ccentricworking faces will arrive on the shoe 16 and force the latter into the seat 11. The cam also has a curved rear face 23 disposed to be engaged by the transverse end 24 of the head 25 of a handle lever 26. The head is pivoted on a bolt 27 within the chamber 15, the rear end of which latter is open. The pivot bolts 21 and 27 are alined with each other on the longitudinal center, of the jaw. lVhen the lever 26 is swung to one side its end 24 exerts a pressure on the rear face 23 whereby the shoe is prevented from The cam is arranged so when rotated of the cam at a point off set laterally from its working faces 22 is caused to exert pressure on the shoe 16, whereby the shoe 1s displaced toward the seat 11 and the dies 19 caused to bite into the article A, It is obvious that an increased rotation of the cam 20 will exert an increased pressure on the shoe, whereby the gripping action will be intensilied. It will be seen that the shoe will engage the object A over an amplified area of the surface ofthe latter, the dies 19 merely indenting the surface suiiiciently to prevent slippage. By this arrangement the article A. which may be a well casing and comparatively thin, will not be crushed, but will be gripped in. a tight and positive manner. In using the wrench the lever 26 will be swung and consequently a slight rotation will be imparted to the jaw prior to the actual gripping of the article. The rotating of. the cam will impart a swinging movement to the shoe which will tend to exert a torsional grip contour of the article A, a frictional engagement will be had and a very quick acting and eiiicient wrench produced. It will be seen that the lever 26 may be swung in either direction to rotate the cam so as to cause the jaw to grip the article A.

What I claim, is:

1. In a wrench, a jaw having a seat, means for holding an article in the seat of the jaw, a curved shoe pivoted in the jaw and adapted to engage an article through the seat of the jaw, and a handle lever for swinging the shoe, through said seat.

2. In a wrench, a jaw having a seat, means for holding an article in the seat of the jaw, a curved shoe pivoted to one side of the jaw and co-acting with the seat in gripping an article, a cam pivoted in the jaw, and a swinging handle lever engaging the cam for forcing the latter into operative engagement with the shoe.

3. In a Wrench, a jaw having a seat, means for holding an article in the seat of the jaw, a curved shoe pivoted to one side of the jaw and co-acting with the seat in gripping an article, a-cam pivoted in the jaw and having an eccentric face for engaging and swinging the shoe when the cam is rotated, and a handle lever engaging the cam for rotating the latter. I

4. In a wrench, a jaw having a seat, means for holding an article in th seat of the jaw, a curved shoe pivoted to one side of the jaw and co-acting with the seat in gripping an article, a cam having an eccentric face and pivoted in the jaw, and a handle lever having a head pivoted in the jaw, the head engaging the cam when the lever is swung at a point olf set laterally from the pivot points of the cam and head, whereby the cam is rotated to cause its eccentric face to engage and swing the shoe.

5. In a wrench, a jaw having a seat and provided with 'a rearwardly extending chamber, a latch link pivoted to the jaw, a curved shoe conforming to the seat and having work engaging dies, a cam pivoted in the chamber of the jaw and having eccentric faces on opposite sides of its center, a head having a transverse end for engaging the cam and pivoted in the jaw chamber, and a handle lever attached to the head.

In testimony whereof I aflix my signature.

ROBERT .A. WVILSON. 

